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1.
Technol Cancer Res Treat ; 23: 15330338241250285, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38802999

RESUMEN

Background: Colorectal cancer is a highly aggressive malignant tumor that primarily affects the digestive system. It is frequently diagnosed at an advanced stage. Cuproptosis is a copper-dependent form cell death mechanism, distinct from all other known pathways underlying cell death, tumor progression, prognosis, and immune response. Although the role of cuproptosis in colorectal cancer has been investigated over time, there is still an urgent need to explore new methods and insights to understand its potential function. Methods: The Gene Expression Omnibus and The Cancer Genome Atlas gene expression data were systematically explored to investigate the role of cuproptosis in colon adenocarcinoma. The weighted gene coexpression network analysis was used to construct a gene coexpression network and identify the critical module and cuproptosis-related genes correlated with colon adenocarcinoma prognosis. A cuproptosis-related genes prognostic signature for colon adenocarcinoma was identified and validated. To validate the identified gene signature, quantitative reverse transcription-polymerase chain reaction was performed. Cell proliferation assays were analyzed by CCK8 and cell cycle detection. In addition, reactive oxygen species assay was also analyzed. Results: Five hub cuproptosis-related genes (Dihydrolipoamide S-acetyltransferase, Cyclin-dependent kinase inhibitor 2A, ATOX1, VEGFA, and ULK1) were screened and a prognostic risk model for predicting overall survival was established based on these genes. The model was successfully tested in the validation cohort and the GEPIA database. Colon adenocarcinoma patients were categorized into high-risk and low-risk groups based on risk scores. The study revealed that patients with higher risk scores were more likely to have a poor prognosis. Moreover, Dihydrolipoamide S-acetyltransferase was a tumor suppressor gene that can induce cell death and affected the redox reactions in the colon cancer cell line. Conclusions: These findings suggest that the newly identified 5-gene signature may serve as a more reliable prognostic factor than clinical factors such as age and stage of disease. These findings offer a theoretical foundation for further investigation into potential cuproptosis-related biomarkers for predicting colon adenocarcinoma prognosis in the future.


Asunto(s)
Adenocarcinoma , Biomarcadores de Tumor , Neoplasias del Colon , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Transcriptoma , Humanos , Pronóstico , Neoplasias del Colon/genética , Neoplasias del Colon/patología , Neoplasias del Colon/mortalidad , Adenocarcinoma/genética , Adenocarcinoma/patología , Adenocarcinoma/mortalidad , Biomarcadores de Tumor/genética , Biología Computacional/métodos , Proliferación Celular/genética , Línea Celular Tumoral , Bases de Datos Genéticas , Estimación de Kaplan-Meier , Masculino
2.
ACS Appl Mater Interfaces ; 16(10): 12149-12160, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38412551

RESUMEN

Photocatalysis driven by plasmon-induced hot carriers has been gaining increasing attention. Recent studies have demonstrated that plasmon-induced hot carriers can directly participate in photocatalytic reactions, leading to great enhancement in solar energy conversion efficiency, by improving the catalytic activity or changing selectivity. Nevertheless, the utilization efficiency of hot carriers remains unsatisfactory. Therefore, how to correctly understand the generation and transfer process of hot carriers, as well as accurately differentiate between the possible mechanisms, have become a key point of attention. In this review, we overview the fundamental processes and mechanisms underlying hot carrier generation and transport, followed by highlighting the importance of hot carrier monitoring methods and related photocatalytic reactions. Furthermore, possible strategies for the further characterization of plasmon-induced hot carriers and boosting their utilization efficiency have been proposed. We hope that a comprehensive understanding of the fundamental behaviors of hot carriers can aid in designing more efficient photocatalysts for plasmon-induced photocatalytic reactions.

3.
Biochem Cell Biol ; 102(1): 85-95, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37921219

RESUMEN

Acute myeloid leukemia (AML) is one of the hematological malignancies with a high recurrence rate. WW domain-containing E3 ubiquitin protein ligase 2 (WWP2) is identified as a pivotal regulator of tumor progression. This study aimed to assess the possible role of WWP2 in AML. Analysis of the GEPIA database indicated an elevated WWP2 expression in AML. We established stable WWP2-overexpressed or WWP2-silenced cells using lentivirus loaded with cDNA encoding WWP2 mRNA or shRNA targeting WWP2. Notably, WWP2 overexpression facilitated cell proliferation and cell cycle progression, which was manifested as the increase of colony formation number, S-phase percentage and cell cycle related protein levels. As observed, WWP2 knockdown presented opposite effects, leading to inhibition of tumorigenicity. Strikingly, WWP2 knockdown induced apoptosis, accompanied by upregulation of pro-apoptosis proteins cleaved caspase-9, Bax and cleaved caspase-3 and downregulation of anti-apoptosis protein Bcl-2. Functionally, we further confirmed that WWP2 overexpression enhanced the NF-κB signaling and upregulated the levels of downstream genes, which may contribute to aggravating the development of AML. More importantly, by co-immunoprecipitation assay, we verified that WWP2 bound to NF-κB-repressing factor (NKRF) and promoted NKRF ubiquitylation. Dramatically, NKRF overexpression abolished the role of WWP2 in facilitating the process of AML. Overall, our observations confirm that WWP2 exerts a critical role in the tumorigenicity of AML, and NKRF is regarded as an essential factor in the WWP2-mediated AML progression. WWP2 may be proposed as a promising target of AML.


Asunto(s)
Leucemia Mieloide Aguda , FN-kappa B , Humanos , Apoptosis , Proteínas Reguladoras de la Apoptosis/genética , Línea Celular Tumoral , Proliferación Celular , Leucemia Mieloide Aguda/genética , FN-kappa B/metabolismo , Transducción de Señal/genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación
4.
J Colloid Interface Sci ; 648: 889-897, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37327631

RESUMEN

The development of photocatalytic reduction of CO2 is hindered by slow surface reaction kinetics due to the high activation barrier of CO2 and the lack of activation centers in the photocatalyst. To overcome these limitations, this study focuses on enhancing the photocatalytic performance through incorporating Cu atoms into BiOCl. By introducing a minute amount of Cu (0.18 wt%) into BiOCl nanosheets, significant improvements were achieved, with a CO yield of 38.3 µmol g-1 from CO2 reduction, surpassing that of pristine BiOCl by 50%. To explore the surface dynamics of CO2 adsorption, activation and reactions, in situ DRIFTS was employed. Theoretical calculations were further performed to elucidate the role of Cu in the photocatalytic process. The results demonstrate that the incorporation of Cu into BiOCl induces surface charge redistribution, which facilitates efficient trapping of photogenerated electrons and accelerates the separation of photogenerated charge carriers. Furthermore, Cu modification on BiOCl effectively lowers the activation energy barrier by stabilizing the COOH* intermediate, thereby turning the rate-limiting step from COOH* formation to CO* desorption and boosting the CO2 reduction process. This work unveils the atomic-level role of modified Cu in enhancing the CO2 reduction reaction and presents a novel concept for achieving highly efficient photocatalysts.

5.
J Phys Chem Lett ; 14(17): 4026-4032, 2023 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-37093583

RESUMEN

Photoelectrocatalytic water splitting using metal sulfides is a promising method for green hydrogen production. However, in situ probing of the hydrogen evolution reaction (HER) on sulfides with excellent performance remains a challenge. Here, we construct Au@CdS core-shell nanoparticles to study the HER on CdS, a typical HER catalyst, by surface-enhanced Raman spectroscopy (SERS) using a "borrowing" strategy. We directly capture the spectroscopic evidence of S-H intermediate under HER condition, further verified by isotopic experiments. Moreover, the population of S-H intermediates is improved by injecting charge carriers through light illumination and the S-H bond is weakened by introducing Pt to form a Au@Pt@CdS structure to change the interfacial electronic structure, both of them resulting in significant HER performance improvement. These findings can deepen the understanding of the HER mechanism and offer strategies for designing of cost-effective HER catalyst with high performance.

6.
Nucl Med Commun ; 44(3): 212-218, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36597726

RESUMEN

PURPOSE: This study aims to investigate which hematopoieticcell populations, clinical factors, and laboratory values are associated with FDG uptake in bone marrow (BM) on FDG PET/CT in patients with autoimmune diseases. METHODS: Forty-six patients with autoimmune disease who underwent FDG PET/CT and BM aspiration (BMA) between 2017 and 2022 were enrolled. The max and mean standard uptake values (SUVmax and SUVmean, SUVs) of FDG in BM, liver, and spleen were measured, and the bone marrow-to-liver SUVs ratios (BLRmax and BLRmean, BLRs) and spleen-to-liver SUVs ratios (SLRmax and SLRmean, SLRs) were calculated. BMA and clinical and laboratory parameters were collected and evaluated for association with BLRs and SLRs. RESULTS: The patients were divided into the Grade II group (20; 43.5%) and Grade III groups (26; 56.5%) according to hemopoietic activity. The BLRmax ( P = 0.021), proportion of granulocytes ( P = 0.011), metamyelocytes ( P = 0.009), myelocytes ( P = 0.024), and monocytes ( P = 0.037) in BM were significantly higher in the Grade II group. Multivariate (stepwise) linear regression analyses showed that the proportion of granulocytes in BM was the strongest and only independent factor ( P < 0.0001) associated with BLRmax with an adjusted R2 of 0.431 in model 1. In model 2, ferritin ( P = 0.018), CRP ( P = 0.025), and the proportion of metamyelocytes ( P = 0.043) in BM were correlated with BLRmax with an adjusted R2 of 0.414. CONCLUSION: The FDG uptake in BM is associated with hemopoietic activity and is regulated by hyperplastic granulocytes, particularly immature metamyelocytes, in patients with autoimmune diseases. Glucose metabolism in the BM correlates with the severity of systemic inflammation.


Asunto(s)
Enfermedades Autoinmunes , Médula Ósea , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Fluorodesoxiglucosa F18/metabolismo , Glucosa/metabolismo , Tomografía de Emisión de Positrones , Estudios Retrospectivos , Radiofármacos/metabolismo
7.
Phys Chem Chem Phys ; 24(43): 26477-26484, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36300484

RESUMEN

Two-dimensional magnetic van der Waals materials provide a fertile platform for the design and control of topological spin textures such as skyrmions. However, despite studies reporting skyrmions in many 2D magnetic systems, those of the hosting van der Waals materials remain limited. Here, via first-principles calculations and Monte Carlo simulations, we propose BiCrX3 as a new family of materials for hosting skyrmions. Due to the large SOC of the X atom and intrinsic inversion asymmetry, an inherent large DMI occurs in all systems, enabling intriguing Néel-type skyrmions. Furthermore, upon applying a moderate magnetic field, isolated skyrmions and skyrmion lattices emerge in our systems, and are robust within a relatively wide temperature range.

9.
Angew Chem Int Ed Engl ; 61(5): e202112749, 2022 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-34806809

RESUMEN

Plasmonic metals under photoexcitation can generate energetic hot electrons to directly induce chemical reactions. However, the capability and fundamental insights of the transportation of these hot electrons at plasmonic metal-2D material interfaces remain unclear. Herein, hot-electron transfer at Au-graphene interfaces has been in situ studied using surface-enhanced Raman spectroscopy (SERS) with atomic layer accuracy. Combining in situ SERS studies with density functional theory calculations, it is proved that hot electrons can be injected from plasmonic Au nanoparticles to graphene and directly penetrate graphene to trigger photocatalytic reactions. With increasing graphene layers, the transportation of hot electrons decays rapidly and would be completely blocked after five layers of graphene. Moreover, the transfer of hot electrons can be modulated by applying an external electric field, and the hot-electron transfer efficiency under electrochemical conditions is improved by over three times in the presence of a monolayer of graphene.

10.
Chemosphere ; 264(Pt 2): 128508, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33045505

RESUMEN

Investigation on the electrode/electrolyte interface of nanotextured electrodes is very challenging but critical to understand the CO2 reduction reactions. Here we present that the nanoporous CuBi2O4 photocathodes coated by a TiO2 overlayer with gradient thickness show improved CO2 reduction performance compared to pristine CuBi2O4. Different activity and selectivity for photoelectrochemical CO2 reduction are observed when the thickness of TiO2 coating layer is set at two extreme values, i.e., less and longer than its Debye length. The CuBi2O4 with a thin TiO2 layer shows higher CO/H2 yield ratio, and the one with a thick layer exhibits lower CO/H2 ratio but higher yield for both CO and H2. All these are elucidated based on the results of Mott-Schottky plots, photocurrent response and SEM/TEM images. Results indicate that the TiO2 overlayer on CuBi2O4 is in favor of the generation and separation of electron/hole pairs, and thus facilitate CO and H2 production, while the nanoporous structure and the nonuniform TiO2 overlayer on CuBi2O4 have a great impact on mass transport, local pH, and exposed active sites and, thereby, on the CO production selectivity.


Asunto(s)
Dióxido de Carbono , Nanoporos , Electrodos , Titanio
11.
Zhonghua Liu Xing Bing Xue Za Zhi ; 35(9): 1058-61, 2014 Sep.
Artículo en Chino | MEDLINE | ID: mdl-25492153

RESUMEN

OBJECTIVE: To explore the effect of blood lipid and lipoprotein ratios on the change of brachial-ankle pulse wave velocity (baPWV) among prehypertensive subjects. METHODS: 11 611 subjects with normal blood pressure (BP) were divided into two groups, which was one with optimal blood pressure (BP<120/80 mmHg) and the other with prehypertension (BP:120-139/80-89 mmHg). Height, weight, baPWV, fasting blood-glucose, TC, TG, LDL-C and HDL-C were detected. RESULTS: The abnormal rate of baPWV in prehypertension group was obviously higher than that in the optimal blood pressure group. For optimal blood pressure group, the abnormality of TG, TC, LDL-C, TC/HDL-C as well as LDL-C/HDL-C, caused the increase of baPWV significantly (P < 0.001). For prehypertensive group, the abnormality of TC and LDL-C caused the significant increase of baPWV (P < 0.001). Results from logistic regression analysis showed that except for age, BMI and fasting blood-glucose, TC/HDL-C increasing was the independent risk factor in optimal blood pressure group, while TG increasing was for the prehypertension group. CONCLUSION: With different normal BP level, both abnormality of blood lipid and lipoprotein ratio were the independent risk factors for baPWV increasing.

12.
Biol Lett ; 7(3): 403-6, 2011 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-21227979

RESUMEN

Giant pandas (Ailuropoda melanoleuca) are an iconic conservation species, but despite significant research effort, do we understand what they really need? Estimating and mapping suitable habitat play a critical role in conservation planning and policy. But if assumptions about ecological needs are wrong, maps with misidentified suitable habitat will misguide conservation action. Here, we use an information-theoretic approach to analyse the largest, landscape-level dataset on panda habitat use to date, and challenge the prevailing wisdom about panda habitat needs. We show that pandas are associated with old-growth forest more than with any ecological variable other than bamboo. Other factors traditionally used in panda habitat models, such as topographic slope, are less important. We suggest that our findings are disparate from previous research in part because our research was conducted over a larger ecological scale than previous research conducted over more circumscribed areas within individual reserves. Thus, extrapolating from habitat studies on small scales to conservation planning on large scales may entail some risk. As the Chinese government is considering the renewal of its logging ban, it should take heed of the panda's dependency on old growth.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Ursidae , Animales , China , Especies en Peligro de Extinción , Teoría de la Información , Árboles
13.
Genetica ; 138(11-12): 1297-306, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21120682

RESUMEN

Anthropogenic habitat loss and fragmentation have been implicated in the endangerment and extinction of many species. Here we assess genetic variation and demographic history in the southernmost population of giant pandas (Ailuropoda melanoleuca) that continues to be threatened by habitat degradation and fragmentation, using noninvasive genetic sampling, mitochondrial control region sequence and 12 microsatellite loci. Compared to other giant panda populations, this population has medium-level genetic diversity based on the measure of both mitochondrial and nuclear markers. Mitochondrial DNA-based demographic analyses revealed that no historical population expansion or contraction has occurred, indicating a relatively stable population size. However, a Bayesian-coalescent method based on the observed allele distribution and allele frequencies of microsatellite clearly did detect, quantify and date a recent decrease in population size. Overall, the results indicate that a population contraction in the order of 95-96% has taken place over the last 910-999 years and is most likely due to anthropogenic habitat loss. These findings highlight the need for a greater focus on habitat protection and restoration for the long-term survival of this giant panda population.


Asunto(s)
Variación Genética , Genética de Población , Repeticiones de Microsatélite , Ursidae/genética , Alelos , Animales , China , Conservación de los Recursos Naturales , ADN Mitocondrial/genética , Ecosistema , Frecuencia de los Genes , Geografía , Modelos Lineales , Densidad de Población
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